SU1278940A1 - Method of single-track start-stop magnetic recording-reproducing - Google Patents

Abstract

The invention relates to magnetic recording and allows to increase the reliability of the reproduction result. The counter 13 measures the time interval between the replay times of the start pulse and the additional start pulse, the last pulse of the counter 13 is transferred to the shift register 17 and shifted by one step. Thereafter, the counter 13 is zeroed and refilled with pulses from the input bus 14 of the reference signal. At the moment of equality of the shift register 17 and the counter 13, the digital comparator 18 outputs a pulse, which is counted by the counter 15. The first pulse from the digital comparator 18 coincides with the start (L impulse. The contents of the counter 15 are equal to the value of the code word. 2 Il.

Description

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The invention relates to magnetic recording, in particular to methods of single-track start-stop magnetic recording-reproduction.

The purpose of the invention is to increase the reliability of the reproduction result.

FIG. 1 and 2 depict block diagrams of respectively recording and reproducing the first parts of the device for carrying out the proposed single-station start-stop magnetic recording-reproduction.

Single-track start-stop magnetic recording-playback according to the proposed method is as follows.

During the recording process, code time intervals are formed, each of which is equal to the number of clock periods of the corresponding code word. Then it records the start and stop pulses, respectively, at the beginning and end of these code intervals. At the same time, the recording of starting and stop pulses is provided by reversing the magnetic recording medium, for example, magnetic tape. In addition, after half the clock period of the code words after recording the starting pulses, additional starting pulses are recorded. The recording of additional starting pulses also provide the remagnetization of the magnetic recording medium. In the process of reproduction, the starting impulses, additional starting impulses and stop impulses are reproduced, as well as the formation of impulses of each code word. The pulse generation of each codeword is performed from the moment of reproducing the additional start pulse to the moment of reproducing the stop pulse through periods, each of which is equal to twice the time interval between the moments of reproduction of the start pulse and the additional start pulse.

The recording part of the device (Fig. 1) contains a frequency divider 1 connected by an input to an input bus 2 of the reference signal, a counter 3 connected to an input 1-pin 4 code words, the first and second triggers 5 and 6, a valve 7 connected by the first input to the input bus 8 start pulses, and a half adder 9 connected by an output to the output bus 10. The first output of frequency divider 1 is connected to the first installation input of the first trigger 5, and its second output to the second input of the valve 7 and to the subtracting input of the counter 3. The output of the valve 7 is connected with the second the installation input of the first trigger 5 and the input of the input of the counter 3. The output of the counter 3 is connected to its input to control the account and to the first input of the half adder 9 connected by the second input to the output

the second trigger 6, the clock input of which is connected to the output of the first trigger 5.

The reproducing part of the device (Fig. 2) contains a pulse selector 11 connected by an input to the input bus 12 of the reproduced pulses, a first counter 13 connected by a clock input to the input bus 14 of a reference signal, a second counter 15 connected to the output bar 16

Q codewords, shift register 17, digital comparator 18 and valve 19. Pulse selector 11 is connected by the first and second outputs to the installation input and the count control input of the second counter 15, respectively, and is connected to the shift input and input of the shift register 17 by a third output. The input bit of the shift register 17 is connected to the output bit of the first counter 13 connected to the first input cis} comparator 18. The digital comparator 18 is connected to the output pin of the second shift register 17 and connected to the clock input of the second counter and to the first input of the valve 19 connected by the second input to the input bus 12 of the reproduced pulses and connected by the output to the installation input of the first counter 13. During recording, the valve 7 on the starting pulse from the input bus s 8 extracts the start pulses from clock sequence supplied from the divider 1

0 frequency, a single pulse that sets the first trigger 5 to a single state and provides the input of a code word from the input bus 4 code words to the counter 3. In this case, the count control input of the counter 3 is unblocked, which leads to the subsequent 1 reading of the units from the contents of the last sequence pulses with a divider 1 frequency. The subtraction of units takes place until the complete reset of the counter 3, at which its account management input is blocked. The pulse sequence from the second output of divider 1 frequency, shifted by half of the clock period relative to the clock sequence from its second output, ensures that the first trigger 5 is set to zero, the signal of which goes to the clock input of the second trigger 6. Second trigger b coBiViecTHO with counter 3 affects half adder 9, which provides a modulo two summation. During playback, the first counter 13 measures the time interval between the replay times of the start impulse and the additional start impulse. At the same time, through an additional start pulse, the code of the first counter 13, the filled pulse M. n from the input chip 14 of the reference signal, is transmitted to the shift register 17 and shifted by one step. Thereafter, the first counter 3 is zeroed out and refilled with pulses from the input bus 14 of the reference signal. At the moments of equality of the shift register 17 and the first counter 13, the digital comparator 18 outputs a pulse, which is counted by the second counter 15. With this, the first pulse from the digital comparator 18 coincides with an additional starting pulse. After the arrival of the stop pulse, the counting in the second counter 15 ceases. The content of the second counter 15 is equal to the value of the corresponding codeword.

Claims (1)

Invention Formula Method for one-stop start-stop magnetic recording-reproduction by recording start and stop pulses, respectively, at the beginning and end of the code intervals, which are formed according to the number of clock periods of code words, reproducing start and stop pulses, and generating pulses of each code pulse. Slot, characterized in that, in order to increase the reliability of the reproduction result, an additional start impulse is recorded after half a clock period after each start pulse is recorded, and each code word is generated from the start of the additional start impulse to the start of the stop impulse through periods, each of which is equal to twice the time interval between the moments of reproduction of the starting pulse and the additional hundred tovogo pulse. t / z. one